Method for concentrating and separating the components of gaseous mixtures



- May 25,1937. E. MAZZA 2,081,406

METHOD FOR CONCENTRATING AND SEPARATING THE COMPONENTS OF GASEOUS MIXTURES Filed April 28, 1934 [b 1/6 for:

[do arao Mazza Patented May 25 1937' UNITED. STATES METHOD FOR CONCENTRATHN'G AND SEP- ARATING THE COMPONENTS OF GASEOUS MIXTURES Edoardo Mazza, Turin, Italy Application April 28, 1934, Serial No. 722,997 In Italy May 5, 1933 1 Claim.

a a stratification both in radial and axial direction is produced in the mixture so that the various components may be separated and conveyed to different places.

An important feature of this invention con-' sists in the fact that the mixture is constantly maintainedin dynamic balance during the concentration and separation of the components of the mixture. The concentration may be intensified by causing the gaseous mass under treatment to pass successively through diflerent conditions of dynamic balance, for instance by varying the general composition of the mixture by successively subtracting parts of the mixture of already modified composition, so that new conditions of dynamic balance are generated and the action ofthe centrifugal force is gradually varied. p

This invention has further for .its'object a simple, efiicient and compact apparatus for carrying out the above described method. Said apparatus is substantially constituted by i a drum rotating on a vertical axis and comprising an annularchamber concentric to the drum axis divided into compartments by means of radial partitions conveniently curved in the way of lmpeller'blades. Eaclrof thsecompartinents is in communication with the interior of the drum through a supply opening in proximity to the concave face of the partitions and with the atmosphere through two delivery openings, the lower one of which is provided between the two partitions and the upper one in proximity to the convex face of the partitions. 'A partition (classifying device) is arrangedbetween the delivery openings and extends from the edge of 5 the inner opening to the wall of the outer cylinder. Said partition is provided with passages for the separated. components placing into com-v munication thesupply section with the delivery section of each compartment; the distance of said passages from the center increasing from the supply towards the delivery end.

.- By this arrangement the mixture of gasesor vapours is impinged by the centrifugal force on 55 the outer-wall oi the drum and its components the various components of the mixture or obtain are separated in layers according to their specific gravity, the specific gravity of the layers increasing from the center towards the periphery. Owing to thedifierent molecular velocities of the components and to the suction produced by the rotation in the delivery section, the lighter gases or vapours (owing also to the movement of the mixture with respect to the drum) pass through the passages. A classification of the components is thus obtained: the heavier com- 10 ponents are collected at the periphery of the supply section where they descend by gravity and are discharged to the outside through an opening provided near .the bottom while the* lighter components are collected in the upper 15 part of the supply section and are conveyed by suction through the passages into the delivery section and are subsequently discharged to' the outside through the upper opening. By suitably controlling the speed of rotation of the drum according to the specific gravity of the components of the mixture, it will be possible to separate all cbmponents of the mixture by passing this latter several times through the. classifier. Or the delivery section may be sub- 25 divided by means of suitably arranged partitions in as many chambers as there are passages for the separated components; said chambers may communicate with the outside at different places,

so that it will be' possible to collect separately 0 concentration 01 said components.

The annexed drawing shows by way of example a constructional form. of the classifier according to this invention; 5

3 Fig. 1 is an axial section of the apparatus. The upper half of Fig. 2 shows a'section on line A--A of Fig. ,1 and the lower half a section on line 3-3 of Fig. 1.

Referring-to the drawing, I is a container in 40 which is rotatably mounted on a vertical axis a classifying drum constituted by a bottom 2, a cover ,3, an outer cylindrical wall 4 and an inner I cylindrical wall 5. All these parts are'mounted on a vertical shaft '6 supported-by a bearing 1 46 compartment and, with the'inslde' ot-the conthe bottom 2 and an opening II in proximity to the cover 3 and to the convex face of the other partition 8 forming the compartment.

The delivery openings H and I2 for the concentrated gases are provided on the wall edges and are of the lowest possible width in the direction parallel to the axis of rotation whiletheir width in the direction perpendicular to said axis is sumcient to permit the full discharge of the concentrated gases without creating highly objectionable counter pressures. It has been found that the highest efliciency is obtainedby reducing the edge of said openings to the lowest possible thickness allowed by the strength of the material. Y I In each compartment is mounted, parallel to the axis of rotation, a row of columns I 3 extending from the edge of the opening I0 opposite to the adjacent partition 8, to a point of the outer wall between the openings H and I2. Said columns are so shaped as to form staggered passages .ll arranged at increasing distances "from the axis rof rotation each being formed by .moments of the rotating parts.

an inner radial part a and an outer flared part b constituting a guide for the fluid threads flowing in the compartment.

-,The passages ll place the supply section I5 in communication with the delivery section l6. The supply chamber 9 projects from the container l and ends in an enlarged part having the form of a.plate l'l carrying the suction and force blades I 8 keyed to the shaft 6.

The container i is subdivided in two superposed chambers I9 and 20 separated from each other by an annular horizontal partition 2| secured to the container wall and loosely embracing a ring 25 fixed to the wall 4 in order to form with the assistance of the centrifugal force ,a fluid tight seal between 'the.-compartments l9 and 20 and to reduce the bending The delivery sections i6 communicate through theopenings II with the chamber l9 provided with a discharge nipple 22 and the supplysections 15 com- ,municate with the chamber '20 provided with a discharge nipple 23 through the' openings l2. when more than two components of the mixture are to be obtained the number of rings 25,

partitions 2i and chambers should be increased accordingly.

The center 'of' gravity should coincide with the intersection of the axis of rotation with the support plane of said rotating mass in order that the gyroscopicaction of the rotating mass (constituted by the classifying rotating drum, plate I! and blades l8) be of full efllciency; therefore the shaft 6 extends under the bearing 1 r and at its lower end is keyed a fly-wheel 24 of ponents, the separating rotating drum is set into rotation. The blades ll effect the suction of the mixture and press and convey this'latter into the supply chamber, from which through the openings it it is' distributed to the supply sections I! of the various compartments.

,In these sections the mixture falls under the action of the blade partitions 8 and is set in rotation; the centrifugal force impinges the components of heavier specific gravity on the outer wall thus producing an annular concentric stratification, the density of which increases from the centre towards the periphery. These layers, owing to the presence of the blades l8 move forward in the sections l5 and are brought to the openings b of the separating passages It. When the inner lighter layers reach'said openings b, owing to their higher molecular velocity in comparison with the heavier layers and to the suction produced by the rotation of the drum The components of lighter specific gravity are conveyed through the openings ll into the chamber l9, from ,which they may be discharged through a nipple 22.

If there is a substantial difference in the specific gravity of the mixture components it will be possible to efiect the separation in a single cycle; if on the contrary said diiference is small, a concentration of the components will be obtained in the first cycle and the operation will be repeated and by controlling the speed of rotation of the rotating separating drum, during the cycles, a substantially complete separation of the various mixture components will be obtained in a few cycles. Q

It is evident that this method and apparatus for concentrating and separating gaseous mixsaid masses about a common vertical axis thereby forming strata of progressively increasing specific gravity from the axis of rotation, withdrawing portions of the lighter constituents in a centripetal direction from each of said segmental gaseous masses along. a plurality of restricted circumferentially spaced and substantially radial paths, progressively more remote from the axis of rotation and separately withdrawing heavier constituents from the lower portion and lighter constituents from the upper portion of each of the masses whereby centrifugal force, gravity and the difference in the molecular velocities of the constituents are utilized to concentrate the mixture into fractions enriched in lighter and heavier constituents.

. EDOARDO MAZZA. 

